1. Field of the Invention
The present invention relates to system for monitoring the deployment of an airbag, and more particularly to a system for monitoring the deployment of an airbag of a motor vehicle.
2. Background Art
Motor vehicles may include one or more airbag modules or deployment systems that deploy an airbag in response to a vehicle impact event. A deployment system may include a monitoring system that monitors deployment of an airbag. Such monitoring systems may detect when an airbag is not fully deployed. An airbag may not fully deploy due to an obstruction, such as an out-of-position occupant, disposed in the airbag deployment path.
Monitoring systems may have various configurations. One type of monitoring system employs a tape that is attached to an interior surface of the airbag. The tape is disposed in a stored position prior to airbag deployment and is pulled by the interior surface when the airbag is deployed. A sensor may detect movement of the tape and generate a signal indicative of the position of the airbag.
Monitoring systems utilizing devices such as tapes may not function properly when the tape is mispositioned during manufacturing or installation. For example, the tape may be partially actuated from its stored position, resulting in a fold or slack disposed between its airbag attachment point and the sensor. This slack region is pulled tight or advanced before subsequent portions of the tape are advanced. Moreover, the tape will not move past the sensor until the slack portion is pulled tight, resulting in inaccurate or untimely detection of airbag deployment and delayed or missed opportunities to alter the airbag deployment sequence.
Before Applicant's invention, there was a need for an improved monitoring system that could accurately detect deployment of an airbag. In addition, there was a need for a monitoring system that could detect slack or mispositioning of a flexible member. In addition, there was a need for a monitoring system that was inexpensive to implement and compatible with high volume manufacturing operations, such as those associated with motor vehicle assembly. Problems associated with the prior art as noted above and other problems are addressed by applicants' invention as summarized below.